Spray booth



June 3, 1941.

A. J. DALTON SPRAY BOOTH Filed May 23, 1940 5 Shee'ts-Sheet l V L. L

INVENTOR.

ATTORNEYS.

BY ALF/FED J; DALTUN M 9 6M June 3, 19 41. J DALTON 2,243,839

SPRAY BOOTH Filed May 25, 1940 s Sheets-Sheet 2 Aum J QALTL/N MrM ATTORNEYS.

June 3, 1941. A. J. DALTON SPRAY BOOTH' Filed May 25, 1940 3 Sheets-Sheet 3 INVENTOR. BY ALFRED J DAL 222v M 2 M ATTORNEYS.

Patented June 3, 1941 SPRAY BOOTH Alfred J. Dalton, Detroit, Micln, aasignor it Industrial Sheet Metal Works, Inc., Detroit, Mich, a corporation of Michigan Application May 23, 1940, Serial No. 336,697

6 Claims.

This invention relates to improved apparatus for removing foreign material such as paint. enamel lacquer, dust, grindings, polishing and burnishing refuse, and other foreign material from air within which it is suspended. If desirable, such foreignmaterial following removal may be salvaged or it may be thrown away.

This invention may be embodied in association with the exhaust system of apaint spray booth or of grinding, burnishing, or polishing machinery or elsewhere. as desired.

Air carrying foreign material in suspension is caused to enter into my improved apparatus through an. inlet and to pass therethrough being exhausted therefrom through a provided outlet. A water shower is produced within the apparatus though other aqueous or, non-aqueous cleaning liquids may, if desired, be used inthe shower,

instead of water and wherever the term water" is used herein it is intended to cover any suitable cleaning liquid.

A series of bailles are so arranged within the apparatus and the water shower creating mechanism is so disposed therein and with respect to the battles and the air is passed therethrough at such a. rate that the air stream picks up water from the shower and throws it into rapid swirling agitation between a pair of spaced superposed baffle elements. The airstream passes through this swirling agitated water shower and the suspended foreign material is swept out of the air by such swirling agitated shower and dropped into a water reservoir therebelow.

The arrangement of, bailies is such that the air stream is successively constricted and expanded and caused to flow at varying rates of travel in a zigzag manner that the bailles act also as water eliminators so that the air issues from the exhaust substantially free from suspended foreign material and water.

Other objects, advantages, and meritorious features of this construction will more fully appear from the following specification, appended claims, and accompanying drawings wherein:

Figure 1 is a front elevation of a machine embodying my invention,

Fig. 2, is a vertical sectional view through the structure of Fig. 1,

Fig. 3 is a side elevation of one of the discs of the water wheel,

' Fig. 4 is a vertical sectional view through a modified form of apparatus,

Fig. 5 is a detailed sectional view through the water shower of Fig. 4 that floods the outer wall of the casing above the air inlet,

7 contains relatively heavy particles, such as would Fi 6 lsa vertical sectional view taken on the same line of Fig. 4 but showing a modified form of construction. and a Fig. '7 is an elevation showing a battery of devices embodying my invention.

As stated, my improved apparatus is adapted to remove air suspended foreign particles whether they be present in the formof lacquer, paint, or the like. Such foreign particles may be present in air exhausted from a paint spray-booth or in 'the form of grindings or refuse" from a machine grinder polishing or burnishing mechanism. In the three modifications illustrated the one shown in Figs. 1 and 2 is that particularly intended-for use in the case of an air stream which be produced by grinding, polishing or burnishing machinery. The structure shown in the modifichamber I6 is separated from the remainder of the casing and air passageway by a wall 20. The water reservoir carries water or any other suitable cleaning fluid to a height indicated in the figures by the dotted line 22. It is understood that this liquid may be of an aqueous or nonaqueous character as may be desired. Alkali cleaning materials may be used in water. Oil or carbon tetrachloride or whatever fluid is desired for use may be employed. The wall 20 of the casing is turned inwardly at the bottom as at 24 forming a baiile like element which terminates within the interior of the casing above a water wheel indicated as 26. i

This water wheel is shown more in detail in Figs. 1 and 3. It comprises a shaft 28 upon which are mounted a series of discs 30 held in axially spaced apart relationship by c0ilars.- This water wheel may be driven by a suitable electric motor not shown in a manner which is well understood. The discs of the wheel dip into the water in the reservoir It as illustrated in Fig. 1 and it will be noted that the upper margins of the discs terminate slightly below the margin of the overhanging bailie 24 as illustrated in Figs. 1 and 2. One of these discs is shown in elevation in Fig.

3. This disc is distorted as at 32 providing laterally projecting flanges which serve as fins to pick up water as the wheel is rotated through the water of the reservoir.

This wheel' is rotated in a counterclockwise direction as indicated by the arrow in Fig. 2 and creates a shower of water between the margin of the baille 24 and the rear wall 34 of the casing. An approximation of the character of such shower is indicated by the long dash lines in Fig. 2. These long dash lines indicate diagrammatically the character of the shower be-,

fore the air stream is drawn therethrough. The short dash lines indicate the character oi: the shower when the air stream is being drawn through the shower.

Air carrying suspended foreign particles enters the machine at the inletl8 and flows downwardly through the compartment l underneath the baflie element 24 between the discs and flows outwardly upwardly through the machine as hereinafter more particularly described. This air stream may be produced by a fan indicated schematically and as by A connected with the exhaust from the machine to draw air through the machine at a rapid rate as hereinafter described.

In the construction shown a wall portion 36 extends downwardly within the reservoirand separates the main portion directly underneath the wheel and forwardly of the wheel from an end portion which is covered by a hinged lid 38. This wall portion thus divides the reservoir into that portion directly underneath the wheel from what might be termed a still water pool or settling tank at one end as is conventional and old in constructions of this kind. The foreign material deposited in the reservoir will therefore tend to collect in this settling tank portion and may be removed therefrom by an operator as desired.

The casing proper superposing the water shower creating wheel is provided with a series of staggered bafile elements 40, 4|, 42 and 43 as shown in Fig. 2. Each of these baflle elements is shown as having a marginal lip 44, These baffie elements are arranged in a superposed staggered series projecting from opposite walls of the casing interiorly thereof and angularly with respect to each other whereby an air stream drawn through the casing is caused to pursue a zigzag path. The air stream is also constricted as it passes through the reduced passageway between the margin of the flange 44 and upper surface of the bafiie element therebelow and as is well understood is speeded up as it passes through this restriction.

As above set forth the air stream flowing through the discs underneath the baflle 24 picks up the water shower indicated by the long dashes and carries it up toward the bafile 40 from which it swirls downwardly against the baille 24 and creates in the restricted zone between the baille 24 and the margin of the lip 44 of baille 40 and toward the rear wall 34 a swirling highly agitated downwardly directed shower of water broken up very fine. This rapid finely broken up shower sweeps the foreign material from the air stream into the water in the reservoir. Very little water is carried above the baflle 40 and practically no water in suspension passes through the upper series of battles and out of the exhaust opening. The bailies therefore serve as water eliminators as well as to remove the foreign material originally entrained with the air stream,

The lip 44 on the bailie 40 as well as the other baflles augments this downward direction of the water shower.

In the construction shown in Fig. 4 the apparatus includes a reservoir l0 and a casing indicated generally by the numeral I2 having exhaust opening l4 as hereinbefore described. The water in the reservoir may stand at level 22 as indicated before. There is a bailie element extending upwardly from the floor of the casing of the reservoir and a baliie element 3 extending \downwardly from the rear wall of the casing into the reservoir as indicated. The front wall of the casing 2| is turned inwardly at 23 as shown particularly in Fig. 4. The four batlie elements 40, 4|, 42 and 43 are provided with a downwardly turned lips 44 as also heretofore indicated. The shower producing mechanism is of a different character to that described in Figs. 1 and 2.

In the construction of Fig. 4 the shower producing mechanism is in the form of a pipe 48 having nozzles or discharge outlets 50 which direct water spray across the casing toward the deflector element 3. It will be understood that this pipe 48 extends across the casing and is provided with these nozzles 50 at spaced intervals throughout its length so that a water curtain in the form of a shower is directed from the pipe from these nozzles against thedeflector plate l3 and as indicated by the long dash lines. Striking the plate l3 the water streams are thrown upwardly against the baiiie plate 4| from which the water showers down as indicated schematically by the long dash lines. Water is pumped through this pipe 48 from a suitable source of supply by mechanism not shown but of a conventional character. Pipe 3| may be used to draw water from the reservoir to maintain a desired water level therein. A float valve, not shown, may be provided to maintain the water level at a predetermined height within the reservoir. This is all conventional structure.

The construction disclosed may be associated with a paint spray booth of any suitable design. In Fig. 6 there is diagrammatically shown a forwardly extending housing and a conveyor may carry parts to be sprayed through such housing. This housing is indicated generally by the numeral 52. Paint may be sprayed upon the parts carried therethrough. This paint would be directed toward the wall 2|.

As is conventional practice, this wall 2| may be showered with water distributed thereon from above. The particular shower mechanism shown here is not conventional but comprises a water spreader plate 54 hinged at 56 to be positioned as shown in Figs. 4 and 5 or upon swinging of the arm 58 to be dropped downwardly to permit removal of the water distributing element or trough 60. This trough 60 is provided with a series of perforations throughout its length indicated as 62 which are adapted to discharge Water into the spreader plate 54. This water overflows a flange 64 on the margin of the spreader plate striking against the angular portion 65 of the wall 2| and flows downwardly over the outer face of said wall. The spreader plate 54 has a skirt 68 which overlaps in close proximity the upper portion of the wall 2| so as to direct the water curtain over its front face. A stop 70 is provided to assist in holding the trough 6|] in position. The spreader plate may be swung downwardly as heretofore described so that any type of trough element 60 may be substituted. Water may be delivered to this trough through a delivery pipe 12 from any suitable source.

A watercurtain is therefore created upon the outer face of the wall II, the water dropping into the reservoir. This water serves to wash down paint particles which strike such outer surface as the air stream impinges it. .Air. is drawn through the casing by a fan A as heretofore referred to in connection with the constructions of Figs. 1 and 2. This is accordingto conventional practice.

In this construction as the air stream is drawn through the casing the water shower which is created by water discharged from the nozzles 50 is picked up and swept upwardly toward the baille 4i and above the baiiie ll creating a swirling agitated water mass in the restricted area between these two bailles which sweeps the foreign material in suspension from the air stream down into the reservoir. Asheretofore described these baflles act also as water eliminators so that the air stream leaving the casing is substantially free not only of foreign material in suspension but of water in suspension. The water shower prior to being picked up by the air stream is indicated diagrammatically by the long dash lines. It strikes against the deflector plate i3 and is thrown up against the battle ll and then downwardly. The short dash lines indicate the swirling agitated shower that is produced when the fast flowing air stream is drawn through the casing.

In Fig. 6 the construction is similar to that of Figs. 4 and 5 in that there is a reservoir in and a superposed casing I 2 having a wall ll which is showered with water in the manner described in connection with the structures of Figs. 4 and 5. Baifle elements 40, ll, 42 and 43 each having downwardly turned lips 44 are similarly provided. In this construction the shower producing mechanism is in the form of a pipe indicated as 48a having nozzles 50a. The reservoir has a battle i I and there is a deflector element l3 all as shown in Fig. 4. The air enters in the same manner and is showered in the same manner as heretofore described and the mechanism may be coupled up with a paint spray booth in a similar manner. This construction differs from the construction of Fig. 4 in the location of the water shower mechanism.

The water shower pipe is directly in the air stream. The construction of Fig. 4 is therefore preferable in that the water shower pipe in this structure is outside of the air stream and is positioned within the space between the baffle 40 which overhangs the shower mechanism and the inturned wall portion 23. In the structure of Fig. 4 such water shower pipe is therefore protected from being fouled by foreign material carried in the air stream.

In the construction of Fig. 6 a water shower is created by water discharged against the inturned wall portion 23 from the nozzles 50a. This shower is picked up by the air stream and the shower is broken up. agitated. and set into a swirling motion above the baiiie 40 and below the baille 4| in the restricted space therebetween in the manner heretofore described in connection with the constructionof Fig. 4 and as shown dia rammatically herein.

Fig. '7 illustrates what might be termed a battery device of several structures such as shown in the earlier figures. For example, a battery of devices as shown in Figs. 4 and 6 might be installed, one device alongside another with exhaust conduits Ii leading from each device and terminating in a main exhaust line Tl.

In each of the constructions set forth the air stream is drawn into the apparatus at a high rate of speed as, for example, at 200 feet a minute. This air stream picks up the water which-preferably is discharged into the shower at a normal rate, which rate would not exceed and probably would be less than that of the air. The shower comprises relatively heavy individual streams. It is relatively sluggish and of slight height and only moderate in character. It is picked up by this air stream and swirled up above the baille that surmounts the shower forming mechanism and forms in the restriction above bination, a water carrying reservoir, walls forming an upright casing superimposing said reservoir having an air inlet at the lower end adjacent to the reservoir and an outlet at the upper end, a series of baflles e nding from opposite sides partially across the interior of the casing in spaced alternately staggered overlapping relationship with the lowermost bailie disposed adjacent to the air inlet, each baifle member being in the form of a flat metal plate attached along one side to a wall of the casing and projecting inwardly into the casing at a downward inclination toward the next lower baille and functioning to cause an upward stream of air through the casing to be deflected from its bottom side downwardly toward the top side of the next lower baille member, means directing a water shower across the air passageway through the casing between the air inlet and the lowermost baflle, a wall within the casing so disposed relativeto the free margin of the lowermost battle as to form a restricted opening therebetween and to the water shower as to deflect it upwardly into said opening, said opening being substantially less than the entrance to the space between said lowermost baiile and the next succeeding baille, said space converging to an outlet of substantially less area than its entrance, and means for causing air to enter the casing at the inlet and flow upwardly therethrough around the baffles at such a velocity that it picks up the water deflected by said wall and carries it through said restricted opening into the area between the lowermost pair of baflles where it is swirled and deflected downwardly against the top side of the lowermost baffle.

2. Apparatus for removing from an air stream iorm of a flat plate arranged at an incline in the casing with upper edge thereof abutting one of said two opposite walls of the casing and with the lower edge free and spaced from the opposite wall of the casing and adjacent baffles to form a restricted opening, certain of said baflies overlapping upon one another and provided on their lower free edges with a' downwardly projecting lip, water discharge means immediately under the lowermost baiiie in said series and arranged to direct a flow of water from under the free edge of the lowermost baflie toward the opposite wall of the casing, a surface within the casing opposite the'free edge of the lowermost bafiie cooperating therewith to define a relatively restricted opening and upon which said flow of water impinges, said surface having such an inclination with respect to the flow of water as to deflect some of the water impinging thereon upwardly through the restricted opening formed by the lowermost baiile and said surface, and means for causing an air stream to enter the inlet to the casing and'travel upwardly through said flow of water adjacent to the inlet and thence upwardly through the series of battles, the downward inclination of said baflles and the provision of the lips on certain of said baiiles causing the air stream to be deflected from the bottom of each baflie toward the top side of the lower bailie as the air stream pursues its tortuous path upwardly in the casing to the outlet.

3. Apparatus for removing from an air stream suspended foreign material comprising, in combination, a water carrying reservoir, an upright casing forming an air passageway having an air inlet at the lower end adjacent to the reservoir and an air outlet at the upper end, a plurality of horizontally extending water eliminating bailies in said casing arranged in vertically spaced apart relationship with the lowermost baflle adjacent to but above the said air inlet, said baflles projecting inwardly from two opposite walls of the casing in alternately staggered relation and at downward inclinations and forming in cooperation with the walls of the casing and with each other a tortuous passage for an air stream moving upwardly therethrough the baflie immediately above said lowermost baflie extending sufficiently far across the casing and at such a downward inclina'tion as to form in cooperation with the lowermost baiile and the opposite wall of the casing a space between the two baliies which converges to a restricted outlet, a surface opposite the inner edge of the lowermost baflle and cooperating therewith to form a restricted entrance to said converging space, means for directing a flow of water across the casing from the inner edge of the lowermost baflle toward said surface such that without any movement of air in the casing the entire flow of water will normally travel generally horizontally across the entrance to said converging space and strike said surface, said surface having such an inclination with respect to said flow of water that it deflects the water upwardly into said restricted entrance, and means causing an a r stream to enter said air inlet and flow upwardly through said horizontally directed flow of water at such a speed that it picks up said water and carries it upwardly from its normal path through said restricted entrance and into said converging space where both the air and the water are caused to be violently swirled around and deflected downwardly by the baflie immediately above the lowermost baille toward the top side of the lowermost baflle.

4. The invention described in claim 3 characterized by the fact that the baflle immediately above the lowermost baiiie is provided with a depending lip along its inner marginal portion which augments the downward deflection of the water toward the top side of the lowermost baflle.

5. Apparatus for removing from an air stream suspended foreign material comprising a water carrying reservoir, an upright casing superposing said reservoir and forming an air passageway having an air inlet-at the lower end adjacent to the reservoir and an air outlet at the upper end, said casing provided interiorly with a pair of vertically spaced baflies extending inwardly from opposite walls of the casing and inclining downwardly such as to form a converging air space therebetween, means for directing streams of water generally horizontally across and immediately adjacent to the entrance to the converging space between said baiiles, a surface disposed to receive said streams of water and so inclined with respect to said streams of water that without any movement of air in the casing the surface acts to deflect the water thus received into the entrance to the converging space between the bailles, and means causing an air stream to enter at the inlet and flow upwardly through said streams of water and through the converging space between said baflies. l

6. Apparatus for removing from an air stream suspended foreign material comprising, in combination, a water carrying reservoir, an upright casing forming an air passageway superimposing said reservoir and having one wall thereof terminating above the level of the water in the reservoir to form an air inlet into the casing, a plurality of horizontally extending water eliminating battles in said casing-arranged in vertically spaced apart relation with the lowermost bailie thereof adjacent to but on a level above the upper edge of said air inlet, said bafiles projecting inwardly in alternately staggered relationship from said wall of the casing providing the air inlet and the opposite wall, a surface opposite the inner edge of the lowermost baflle cooperating therewith to form a restriction in the air passageway, a series of nozzles arranged in horizontal spaced apart relation immediately under the lowermost baflie and above the level of the upper edge of said air inlet and adapted to project streams of water generally horizontally across the casing from under the inner edge of the lowermost bailie against the surface cooperating therewith to form said restriction, and means causing air to enter said inlet and flow upwardly through said streams of water and through said restriction at a rapid rate.

ALFRED J. DALTON. 

